Use Windows SSPI API to generate kerberos ticket for JDBC SSO (#441)

* Use Windows SSPI API to generate Kerberos ticket for JDBC SSO

* Use 2 space characters for indentation

* Comment out setting sun.security.jgss.lib property, it is not needed anymore

* Use set insted of export on Windows

* Typo fixes

Author: ibre5041

java/jdbc/ConnectionSamples/GSSAuthSSPIConnectSample.java

@@ -0,0 +1,136 @@
+/*
+  Copyright (c) 2025, Oracle and/or its affiliates.
+
+  This software is dual-licensed to you under the Universal Permissive License
+  (UPL) 1.0 as shown at https://oss.oracle.com/licenses/upl or Apache License
+  2.0 as shown at http://www.apache.org/licenses/LICENSE-2.0. You may choose
+  either license.
+
+  Licensed under the Apache License, Version 2.0 (the "License");
+  you may not use this file except in compliance with the License.
+  You may obtain a copy of the License at
+
+  https://www.apache.org/licenses/LICENSE-2.0
+
+  Unless required by applicable law or agreed to in writing, software
+  distributed under the License is distributed on an "AS IS" BASIS,
+  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+  See the License for the specific language governing permissions and
+  limitations under the License.
+*/
+
+/*
+  DESCRIPTION
+  This sample shows how to use SSO uging Kerberos on Windows.
+  Since WIN2019 allowtgtsessionkey registry key is not available 
+  and the only option how to acces Kerberos TGT is via Java's SSPI bridge.
+	
+  PREREQUISITIES
+  - Configure Kerberos authentication for Oracle database as described here:
+  https://blog.pythian.com/part-4-implementing-oracle-database-single-sign-on-using-kerberos-active-directory-and-oracle-cmu/
+      
+  - Create DB user identified extenally as:
+  CREATE USER <AD LOGIN> IDENTIFIED EXTERNALLY AS '<AD LOGIN>@<AD REALM>';
+  GRANT CONNECT TO <AD LOGIN>;
+     
+  - Check your Windows has generater Kerb tickets during logon
+  klist tgt
+  klist
+     
+  - Connect to database using this program. 
+  Java's SSPI bridge(sspi_bridge.dll) should be used to renerate required Kerberos ticket for SSO.
+
+   NOTES
+   Use JDK 13 and above on Windows. Check presence of sspi_bridge.dll in JDK intalation.
+
+   MODIFIED    (MM/DD/YY)
+   ibre5041    18/04/2025 - Creation
+*/
+
+package kerb;
+
+import java.sql.ResultSet;
+import java.sql.Statement;
+
+import java.util.Properties;
+
+import org.ietf.jgss.GSSCredential;
+import org.ietf.jgss.GSSManager;
+import org.ietf.jgss.GSSName;
+import org.ietf.jgss.Oid;
+
+import oracle.jdbc.OracleConnection;
+import oracle.jdbc.OracleConnectionBuilder;
+import oracle.jdbc.pool.OracleDataSource;
+import oracle.net.ano.AnoServices;
+
+public class GSSAuthSSPIConnectSample {
+  // This should return your AD LOGIN
+  String username = System.getProperty("user.name");
+  // This should return your AD KERBEROS REALM
+  String domain = System.getenv("USERDNSDOMAIN");
+  // Your Database JDBC URL here
+  String url = "jdbc:oracle:thin:@//dbhost1:1521/DBSERVICE";
+
+  public GSSAuthSSPIConnectSample() {
+  }
+  
+  public void doit() throws Exception
+  {
+    // Use env variable SSPI_BRIDGE_TRACE=1 in order to trace Java's sspi_bridge.dll plugin
+    // set SSPI_BRIDGE_TRACE=1
+    
+    // Various useful tracing options
+    // System.setProperty("oracle.jdbc.Trace", "true");
+    // System.setProperty("sun.security.krb5.debug", "true");
+    // System.setProperty("sun.security.spnego.debug", "true");
+    // System.setProperty("sun.security.jgss.debug", "true");
+    // System.setProperty("java.security.debug", "true");
+    // System.setProperty("sun.security.nativegss.debug", "true");
+
+    // Activate SSPI bridge, your Kerberos token will be created using Windows SSPI API
+    System.setProperty("sun.security.jgss.native", "true");
+    // Uncomment this this line for JDK 11, for newer JDK versions this value should be default
+    // System.setProperty("sun.security.jgss.lib", "sspi_bridge.dll");
+
+    Oid krb5Oid = new Oid("1.2.840.113554.1.2.2");
+    GSSManager manager = GSSManager.getInstance();
+
+    GSSName srcName = manager.createName(username + "@" + domain, GSSName.NT_USER_NAME);
+    GSSCredential cred = manager.createCredential(srcName
+						  , GSSCredential.DEFAULT_LIFETIME
+						  , krb5Oid, GSSCredential.INITIATE_ONLY);
+
+    Properties prop = new Properties();
+    prop.setProperty(AnoServices.AUTHENTICATION_PROPERTY_SERVICES, "(" + AnoServices.AUTHENTICATION_KERBEROS5 + ")");
+    prop.setProperty(OracleConnection.CONNECTION_PROPERTY_THIN_NET_AUTHENTICATION_SERVICES,"( " + AnoServices.AUTHENTICATION_KERBEROS5 + " )");
+    prop.setProperty(OracleConnection.CONNECTION_PROPERTY_THIN_NET_AUTHENTICATION_KRB5_MUTUAL, "true");
+
+    OracleDataSource ods = new OracleDataSource();
+    ods.setURL(url);
+    ods.setConnectionProperties(prop);
+    OracleConnectionBuilder builder = ods.createConnectionBuilder();
+    OracleConnection conn = builder.gssCredential(cred).build();
+        
+    String auth = ((OracleConnection)conn).getAuthenticationAdaptorName();
+    System.out.println("Authentication adaptor:"+auth);
+
+    String sql = "select user from dual";
+    Statement stmt = conn.createStatement();
+    ResultSet rs = stmt.executeQuery(sql);
+    while (rs.next())
+      System.out.println("whoami: " + rs.getString(1));
+
+    conn.close();
+  }
+
+  public static void main(String[] args) {
+    GSSAuthSSPIConnectSample test = new GSSAuthSSPIConnectSample();
+    try {
+      test.doit();
+      System.out.println("Done");
+    } catch (Exception e) {
+      e.printStackTrace();
+    }
+  }
+}